Carrier board transfer system for handler that supports testing of electronic devices and method for transferring carrier board in chamber of handler

A system for transferring a carrier board in a chamber of a handler that supports the testing of electronic devices, comprising:

• an transfer apparatus for transferring the carrier board at a transfer start position selectively to one of at least one or more mid transfer positions and a transfer final position;
• and
• at least one or more supporting apparatuses for supporting or releasing the carrier board located at the at least one or more mid transfer positions so that a carrier board transferred to one of at least one or more mid transfer positions by the transfer apparatus is supported on a corresponding supporting apparatus and a carrier board to be transferred by the transfer apparatus to another of at least one or more mid transfer positions or the transfer final position is released from the corresponding supporting apparatus,
• wherein the transfer apparatus is configured to transfer the carrier board at the transfer start position selectively to one of at least the one or more mid transfer positions and the transfer final position without transfer stop time period, respectively, and wherein, if carrier boards in the chamber are located spaced apart from each other without transferring outside the chamber allowing no carrier board exists at one or more mid transfer positions, the transfer apparatus is configured to maintain a preceding carrier board at current position thereof and to transfer a following carrier board in a circulating direction of the preceding carrier board to gather the carrier boards located spaced apart from each other in the chamber.